Abstract

Indoor climbing is a worldwide sport with particular physiological and physical demands. With this study, it was aimed to investigate the effects of indoor climbing on oxidative stress, antioxidant levels and hematologic parameters. All results in the study were analyzed via using non-parametric Wilcoxon test with Statistical package for Social Sciences version 17 for Windows, with p<0.05 as the criterion for significance for all statistical comparisons. Fifteen voluntary male students whose average age is 22,35 ± 2,65 years old, participated in this study. These subjects were climbed 30 ± 1,25 times during eight weeks. Blood samples were collected at rest, 24h before, and 24h after climbing protocols to analyze total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) and hematologic parameters [Hemoglobin (Hb), hematocrit (Hct), platelet (Plt) and leukocyte (Wbc)]. Resting heart rates were measured at the same time. According to our findings, TOS (1,47 ± 0,06, 1,51 ± 0,02) (P:0.042) significantly increased, TAS (1,56 ± 0,04, 1,52 ± 0,03) (P:0.036) significantly decreased and OSI (0,94 ± 0,02, 0,99 ± 0,05) (P:0.014) significantly increased with climbing. There has been no statistically relation among the hematologic parameters. Data demonstrate that indoor climbing leads to increased plasma oxidative stress in sedentary individuals and can affect the athletes performance negatively.

Keywords

Introduction

Indoor climbing is the most rapidly growing type of
climbing and is now recognized as a modern competitive
sport as well as a mode of fitness exercise. Climbing has
been described as a vigorous activity that demands muscular
power and strength, flexibility, and aerobic endurance
[1]. It is reported that indoor climbing is adequate
for increasing cardiorespiratory fitness and muscular
endurance [2].

Although numerous studies regarding the beneficial effects
of physical activities have been conducted in the
past, there are also some others about the negative effects
in more recent years [3]. Urso and Clarkson, in their
study, established a link between physical exercise, elevated
O2 consumption, and free radical production [4].
Oxidative stress can be defined as an imbalance status
between the radical oxygen species production and the antioxidant defence mechanism of the living organisms
which in turn results in direct or indirect cellular damage
[5].

It has been suggested that especially acute and intense
exercises lead to oxidative stress, whereas regular endurance
practices may decrease the exercise-induced oxidative
stress and muscular damage and can enhance the
antioxidant defense capacity [6]. There are various enzymatic
and non-enzymatic antioxidant defense mechanisms
in order to protect cell organelles and plasma membrane
from the deleterious effects of free radicals [7]. The physiologic
impact of exercise at various durations and intensities,
including measurements of hematologic parameters,
has been previously investigated [8,9].

In the literature, it has been reported that exercise gives
rise to oxidative stress. Beside the negative effects of
acute and irregular exercise, it is suggested that physical
activities achieved in a regular fashion may lead to a dec rement in lipid peroxidation [10]. In more recent past, it
has been emphasized that TOS and TAS measurements
and evaluation can give more accurate results rather than
a specific parameter look-up [6]. For this reason, we decided
to evaluate TOS and TAS parameters in blood specimens
collected from the participants.

The amount of scientific research that addresses the physiological
demands of indoor climbing is relatively small.
To date, only a few studies have compared the physiological
characteristics of climbers with differing climbing
ability [11]. It is evident that more research is needed to
further clarify the physiological demands of indoor climbing.
Thus, the main purposes of this study were to analyze
the effect of indoor climbing exercise on plasma oxidative
stress, antioxidant levels, hematologic parameters and
heart rate responses before and after the climbing in sedentary
individuals.

Materials and Methods

Study design

This is an observational analytic study.

Subjects

Fifteen voluntary male students whose average age is
22.35 ± 2.65 years old, participated in this study after
being informed about the aims, experimental protocol,
and procedures, and after providing written consent. Out
of 37 students, 15 participated in the study on a voluntary
basis. No sampling was made in the study.

Eligibility criteria: All university students, between 18-25
years old, who visited Suleyman Demirel University
Closed Spore Hall during the given dates were admitted
to study. Being a student in the university and visiting the
hall were the inclusion criterias. Exclusion criterias were
making any kind of sports, smoking cigarette and having
a chronical disease.

Study duration: Study was performed between April-
June 2011, in a three months period.

The climbing wall contained routes set upon portions of
the wall that were strictly vertical or contained an overhang
obstacle. In the beginning of the protocol, all of the
subjects were familiar with each of the individual routes.
The height of the wall was measured at 14m. These routes
were considered as being achievable by beginner climbers.
These subjects were climbed 30±1,25 times during
eight weeks.

Physiological and Biochemical Measures

Heart rate (HR) was measured immediately prior to each
climb and each the top of the climbing. A Polar RS400 HR monitor (Polar Electro Inc., Finland) was used to
assess HR. Blood samples were collected at rest, 24h
before and 24h after climbing protocols. All the venous
blood samples were taken by conventional clinical procedures,
using EDTA as an anticoagulant. TOS, TAS, OSI
and hematologic parameters [Hemoglobin (Hb), hematocrit
(Hct), platelet (Plt) and leukocyte (Wbc)] were
analized in blood samples.

Measurement of the total oxidant and antioxidant status

Total antioxidant status (TAS) and total oxidant status
(TOS) levels were measured spectrophotometrically using
a commercial kit (Rel Assay Diagnostics, Gaziantep,
Turkey) by the Erel methods [12,13]. These methods are
automatic and colorimetric. The TAS measurement method
is based on the bleaching of the characteristic color
of a more stable 2,2-azino-bis (3-ethylbenzthiazoline-6-
sulfonic acid) radical cation by antioxidants. The TOS
method is based on the oxidation of ferrous ion to ferric
ion in the presence of various oxidant species in an acidic
medium and the measurement of the ferric ion by xylenol
orange. The TAS and TOS results were expressed in
mmol Trolox equivalent/L, μmol H2O2/L and mg/dL,
respectively, and the precision error of this assay is lower
than 3%.

Statistical Analysis: Statistical package for Social Sciences
version 17 for Windows used for statistical analysis.
The data were presented as means ± standard error of
mean. All results in the study were analyzed via using
non-parametric Wilcoxon test, with p<0.05 as the criterion
for significance for all statistical comparisons.

Results

All subjects were previously familiarized with the indoor
climbing and laboratory protocol carried out in the two
data-collection sessions. The mean anthropometric characteristics
of the climbers are shown in Table 1.

Table 1: Anthropometric characteristics of the climbers.

The mean TOS, TAS and oxidative stress index
(OSI=TOS/TAS) are shown in Table 2. TOS was significantly
higher than before the climbing and after the
climbing (p:0.042). But, TAS was significantly lower
than before the climbing and after the climbing (p:0.036).
OSI was also significantly higher than before the climbing
and after the climbing (p:0.014).

The mean resting heart rate and heart rate at the top of the
climbing are presented in Table 4. Resting heart rate was
significantly lower than before the climbing and after the
climbing (p:0.032). Heart rate at the top of the climbing
was significantly lower than first day the climbing and
last day the climbing (p:0.024).

*: non-parametric Wilcoxon test
Table 4. Effect of Indoor Climbing on Resting Heart Rate and Heart Rate at the Top of the Climbing.

Discussion

In this study, the relationship between indoor climbing
and oxidative stress in sedentary individuals has analyzed
during eight weeks. Data show that indoor climbing decreased
plasma TAS and increased plasma OSI. In accordance
with other studies, dealing with metabolic responses
to indoor climbing; our data clearly confirm that
a substantial contribution from the aerobic metabolism
fulfills energetic needs for indoor climbing [14]. The
significant increase observed 24h after the climbing exercise
seems to demonstrate additional free radical production
and an overwhelming of the antioxidant capacity.
This increase in OSI observed after the climbing exercise
might be explained by a marked decrease in plasma TAS.

We found that plasma TAS significantly decreased after
the climbing exercise. As an integrated parameter that
considers the cumulative status of some different antioxidants
present in plasma, TAS provide an insight into the
delicate in vivo balance between oxidants and antioxidants.
Previously, it has been shown that both halfmarathon running in trained male runners and treadmill
running until exhaustion induced increases in TAS [15].
Like our findings, Anuhadra et al. have reported a decrease
in non-enzymatical antioxidant activity after six
weeks of aerobical exercise in rats [16]. In another study
by Robertson et al, conducted on antrenary and sedantery
individuals; it has been reported that erytrocyte superoxide
dismutase (SOD) activity is lower in sedantery group
compared to those of the antrenary group, which could be
related to metabolical speed rate and free oxygen species
production [17]. According to our findings, a functional
decrease is likely to occur in non-enzymaticals antioxidants
as a result of interaction with oxidants. Thus, we
think that decrease in TAS levels can be attributed to the
utilization of TAS during the neutralization process of the
oxidants, which increase following the oxidant stress, by
various reactions.

In this regard, it is likely that the increased oxidative
stress observed during climbing exercise might have contributed,
at least in part, to this free radical generating
system. The imbalance between antioxidant capacity and oxidant production induced by climbing exercise was also
supported by some biomarkers of plasma oxidative damage
representative of an ongoing pathophysiological
process associated with oxidative stress. In a study conducted
on 14 male platform climbers, Magalhaes et al
have reported that MDA levels have significantly increased
just one hour after the exercise [18]. Lovlin et al
have indicated via performing bicycle ergometry test that
lipid peroxidation increased in plasma and erytrocyte
membranes during a moderate level exercise [19]. Exercise
type, duration and intensity of participants' gender
and qualifications, the periods before and after exercise,
measurement differences in methods and tissue differences
are the some possible causes for the changes in
exercise-related TOS and TAS.

In our study, resting heart rates after climbing are significantly
decreased compared to the rates before climbing.
In addition, at the last day of the climbing exercise, on the
top of the wall heart rates are significantly decreased
compared to the first day on the top rates. Climbing imposes
a physiological stress on the climber. However,
climbers heart rates decrease with increasing of the climbing
number and individual skills. Eight-week-long aerobic
exercise climbing reduces heart rate speeds. These findings
suggested that skill and technique play an important
role in determining the energy cost of climbing, which in
turn could influence the heart rate response. Janot et al
study supports our finding by a significant decrease in HR
from 179 to 159 beats /min [20]. The findings of this
study may be beneficial to indoor climbing instructors.
This information can aid in designing a climbing program
to fit the individual needs of climbers based on their overall
skill and fitness level.

Furthermore, in our study that has also investigate hematologic
parameters before the climbing and after the
climbing. There has been no statistically relation among
the hematologic parameters. Similar to our results, in
some studies show that the Hb, Hct, Plt, and Wbc levels
aren’t change immediately after exercise. However, in
some studies reported significant differences in hematological
parameters [8,9]. This differs from some previous
reports and the reasons are unclear, but could relate to
differences in exercise regimens, participant age, or timing
of sample collection, which in this study was closer to
the end of the exercise period than a previous study.

From the study, it is concluded that, indoor climbing exercise
induces plasma oxidative stress and this stress may
be exacerbated when the exercise is irregular. Moreover;
antioxidant enzymes that reduce oxidative stress during
exercise, are mostly associated with exercise training.
There is only little certain evidence about antioxidant
supplementation that they are beneficial for athletic performance.
Besides; it seems certain that dietary antioxidants
have positive effect, they can reduce the oxidative damage to muscles and other tissues caused by exercise.
Nowadays; long-term effects of antioxidant supplementation
are not fully understood and this subject must be
investigated. According to our knowledge; it may be
beneficial for individuals performing regular heavy exercise.

Limitations

Small sample size and non-probability sampling resulting
in potential selection bias and hence poor external validity
of the study were the main limitations of the study.